Nd: YVO4 crystal belongs to the tetragonal system, positive uniaxial crystal. Nd: YVO4 crystal has been extensively identified as an important laser material since its advancement in 1966.
Nonetheless, the researchers found defects in the scattering center, absorption color center, and so on. It is, as a result, difficult to grow premium crystals of the dimension needed for a flash pump.
Thankfully, it has excellent absorption and also gains to the wavelength of diode radiation. And also the transmission section is substantial. The output laser has great polarization attributes. These are enough to cover the shortcomings of its small development size.
Advantages
Nd: YVO4 crystal has excellent properties. Compared to another commonly utilized Nd: YAG crystal (neodymium-doped yttrium aluminum garnet crystal), its pump broadband is much more substantial. The absorption transmission capacity efficiency is higher. The promoted discharge cross-section is a lot more comprehensive and has outstanding development worth. Nd: YVO4 crystals are utilized together with nonlinear optical crystals such as LBO crystals, BBO crystals, KTP crystals, and so on. It can understand frequency-doubling conversion and adjust functioning wavelength. The all-solid-state laser constructed from Nd: YVO4 crystal can outcome near-infrared light, green light, blue light, ultraviolet light, and so forth.
- Regarding 808 nm pump bandwidth, about the Nd: YAG 5 times
- The area at 1064 nm of the boosted exhaust of radiation is an Nd: YAG three times.
- Light damages limit is low, high incline effectiveness
- Uniaxial crystal axis, the result of linear polarization
Weak points
Compared with the standard Nd: YAG crystal, Nd: YVO4 has the advantages of a much more substantial absorption coefficient, higher emission cross section, polarization absorption as well as discharge features, bigger absorption data transfer, and also ignorance to the temperature level adjustment of the diode. Therefore, it is widely made used in LD-pumped solid-state lasers.
However, it has a big emission cross-section and a short upper energy lifetime. The energy storage capacity of Nd: YVO4 is a lot less than that of Nd: YAG. Not conducive to high energy, peak power of the Q – switched over pulse output. Their advantages are limited to continuous wave outcome, high average control, and high conversion performance.
Additionally, the thermal conductivity of Nd: YVO4 is very little, only half that of Nd: YAG. As a result, it is not for accomplishing high-power continuous wave output.
Apply
Neodymium-doped yttrium vanadate (Nd: YVO4) crystal is a sort of laser crystal with exceptional efficiency, which is appropriates for producing a laser diode pump, specifically a low-power laser. Compared with Nd: YAG, Nd: YVO4 has a greater absorption coefficient as well as a bigger stimulated discharge cross-section.
Laser diode-pumped Nd: YVO4 crystals are combined with LBO, BBO, KTP and other crystals with high nonlinear coefficients. It can achieve far better frequency-doubling conversion effectiveness. It can outcome near-infrared, green, and also blue ultraviolet and also solid-state lasers.
Nd: YVO4 crystals can be extensively utilized in optical communication, industrial laser handling, laser varying, semiconductor discovery, data storage space, screen, laser printing, medical inspection, machinery, clinical research as well as other fields.
Furthermore, Nd: YVO4 diode-pumped solid-state lasers are rapidly replacing standard water-cooled ion lasers and also lamp-pumped lasers on the market, specifically in terms of miniaturization and also single longitudinal setting outcome.
In the 21st century, several downstream markets of Nd: YVO4 crystal is flourishing, and the application variety of Nd: YVO4 crystal is regularly expanding with apparent efficiency benefits.
Growth method
In the 1960s, Nd: YVO4 crystal was developed. It was drawn out from salt metavanadate melt by the air conditioning technique. The size of the Nd: YVO4 crystal expanded by this approach was small. Since then, the growth procedure of Nd: YVO4 crystal has actually been advanced, such as the Zhilar method, flame melting method, floating zone development method, Bryman method, and also the pull method. Presently, the growth approaches of Nd: YVO4 crystal are different. The drawing technique is the mainstream Nd: YVO4 crystal growth procedure, which can expand big, top-notch crystals.
Pulling method
Nd3+: YVO, crystal melting point is extremely high (about 1820 ℃), must utilize gold-dependent crucible growth, gold-dependent crucible will be oxidized at heat, must utilize a neutral gas (hydrogen) to shield the crucible.
By doing this, growing in an anoxic environment, the dissolved part will decompose into low-priced vanadium oxide (part of YVO4 will disintegrate right into YVO3), and also oxygen shortage will occur in the crystal, resulting in the generation of the color centre.
Growing in an oxygen-rich atmosphere will lead to severe oxidation of the crucible. The lowered episcopes form incorporations inside the crystal. This will certainly cause strong melt volatilization, causing the part discrepancy.
By utilizing different growing atmospheres in various phases, the oxygen deficiency in the crystal can be supplemented, the volatilization of raw materials can be inhibited, the single-phase growth of the crystal can be ensured, and also the crystal can not be blackened or scattered as a result of oxygen shortage because of hypoxia.
